Question

Sebastian wants to write the chemical formula for phosphorus tetraoxide. He identifies the chemical symbols as
and
. Which additional step will he take in his process?
Responses

identify the elements involved as potassium and oxygen
identify the elements involved as potassium and oxygen

add a subscript of
after the
add a subscript of 4 after the cap o

write the chemical symbols, in order, as
write the chemical symbols, in order, as OP

use the prefix tetra before oxygen
use the prefix tetra before oxygen

Answer 1

Add a subscript of 4 after the O — the prefix "tetra-" means four oxygens, so the formula is PO4.